Figure 4 shows the stress-strain curves of the FFRCs under quasi-static and SHPB compression experiments. The simplified Johnson-Cook model (Equation (2)) was used to describe the dynamic rate-dependent constitutive behavior of the FFRCs.
Conclusions
Effect of post-curing temperature on mechanical properties of a flax fiber reinforced epoxy composite.Compos. Analysis of low velocity impact on flax/PLA composites using a strain rate sensitive model.Compos.
Uniaxial Tensile Behavior of Carbon Textile Reinforced Mortar
- Introduction
- Materials and Methods 1. Materials
- Results and Discussion
- Conclusions
The first tear stress and tensile strength of the TRM samples without and with steel fibers are shown in Figure 12. The first tear stress and tensile strength of the prestressed TRM samples are shown in Figure 19.
Investigation of Shear-Induced Deformation of
Reinforcing Textiles by Optical Measurement Devices
Materials and Methods
This allows the reinforcing wires to rotate and transfer force from the photo frame to the sample (Figure 3). Image processing software supported by OpenCV calculated the laser beam deflection curves for each individual time step.
Results
Deviations of approximately 20% in the shear force/shear angle curve are due to semi-finished properties caused by fabric construction. Experimental analysis of the influence of stress on the plane shear behavior of woven composite reinforcements.Compos.
Piezo-Sensitive Fabrics from Carbon Black
Containing Conductive Cellulose Fibres for Flexible Pressure Sensors
Experimental
The electrical resistance of yarn samples was measured to characterize the conductive behavior of the fibers in a longitudinally oriented arrangement. The results in Figure 6 demonstrate the pressure sensitivity of the electrical resistance of a needle punched fiber non-woven material in the low pressure area between 200 and 1000 Pa. These fibers contributed to the recovery of the compressed fiber non-woven fabric during the relaxation.
The pressure sensitivity of the electrical resistance of the two different nonwovens was studied in three repetitive load/relax cycles. The mechanical stability of material A and material B led to a rapid recovery of electrical resistance when the pressure was reduced to the lower limit (Figure 8). The influence of the electrical resistance of the connections to the signal processing device would then be negligible.
Repeated load/relaxation cycles demonstrated the repeatability and durability of the sensor mat and the stability of the signal.
Dielectric Characterization of Non-Conductive
Fabrics for Temperature Sensing through Resonating Antenna Structures
Results and Discussions
The thermal test campaign consists of ten measurements of the resonance frequency for each temperature step (20◦C, 30◦C, 40◦C, 50◦C to 60◦C). All results are shown in the first row of the first column of Tables 4 and 5. At the thermal threshold, the standard deviation of the resonance frequency also showed a larger standard deviation.
By the same mathematical approach as in 3.2.1. to follow, the equivalent change in the dielectric constant is equal to 1.67×10−2. Final results are summarized in the first row of the second column of both tables, Tables 4 and 5. The set of results is listed in the second row of the second column of Tables 4 and 5.
Morton, W.E.; Hearle, J.W.Physical Properties of Textile Fibres, 4de uitgawe; The Textile Institute CRC Press Woodhead Publishing Ltd.: Shaston, Verenigde Koninkryk, 2008.
Textile Display with AMOLED Using a Stacked-Pixel Structure on a Polyethylene Terephthalate
Fabric Substrate
Design of the AMOLED Panel with a Stacked-Pixel Circuit
The switching OTFT (SW OTFT) was activated by applying a scan voltage (Vscan) to the gate of the SW OTFT. Since the mobility of the OTFTs was less than 1 cm2/V·s, a large channel width-to-length ratio (W/L) was required to supply a large current, as described above. Therefore, the aperture ratio was generally less than 20% when the OTFT and OLED were placed in the same plane; this is called a side-by-side structure [22].
In this study, the aperture ratio was improved by using a stacked pixel structure, placing the OLED above the pixel circuit of the OTFTs, as shown in Figure 1b. Next, a protection layer (PL) must be inserted between the OTFT circuit layer and the OLED layer to prevent the OTFT circuit from being damaged by the OLED processes running above it. The PL must not affect the OTFTs below and must also have self-patterning ability.
The channel width of the DR OTFT and the SW OTFT are designed to be W=180×L and 34×L, respectively.
Fabrication
As described in the previous section, a PL was deposited on the circuit layer of the OTFTs to assemble the OLED on it. W-PVA was applied to protect pentacene OTFTs from organic solvent damage by PA. PA protected the PVA bilayers and OTFTs from the effects of the OLED process.
The PVA solution was centrifuged on the plate containing the OTFT circuits at 1000 rpm for 20 s and air dried for 30 min. Then, a d-PVA solution formed by mixing 0.03 wt. % ammonium dichromate with w-PVA solution spin-coated onto w-PVA film. The PA film was patterned through holes for interconnecting OTFTs to OLEDs with UV exposure for 30 s, developed for 40 s, and then hard-baked at 130 °C for 60 min.
Silver was evaporated on the patterned PA layer for the anode electrodes in the OLED, and another PA was spin-coated on the Ag electrodes and patterned to define the OLED area.
Results and Discussion
Representative transfer curves are plotted according to the different mixing ratios of the PA solutions. The high performance of the OTFTs was degraded after PL was deposited on them. Although the performance of the DR and SW OTFTs was degraded after deposition of PL, the performance was still able to operate the AMOLED panel.
The overlap light occurred due to the smaller pixel pitch (280μm) and brighter luminance of the OLEDs caused by the larger on-state current (40μA @ VGS=−10 V) of the DR OTFT. The aperture ratio was 48%, roughly 2.5 times that of side-by-side pixels. The high aperture ratio in the AMOLED panel was successfully achieved using the stacked pixel structure, which was made possible due to the PL between the OTFT and OLED pixel circuit, as well as the improved performance of the OTFTs using CNT/Au (5 nm) hybrid electrodes for the S/D and PA dielectric contacts.
Three key technologies were used: a planarization process on the rough PET substrate; inserting a protective layer (PL) between the OLED and the pixel circuit of the OTFTs; and the use of hybrid CNT/Au (5 nm) electrodes for the S/D contacts along with PA for the gate dielectric of the OTFTs.
Surface Modification of Polyester-Fabric with
Hydrogels and Silver Nanoparticles: Photochemical Versus Gamma Irradiation Methods
Bacterial growth inhibition was assessed in triplicate using samples inoculated with photochemical (UV) or gamma irradiation, with or without AgNPs. An important step in the synthesis of hydrogels on PET fabric is the initiation of polymerization. Scheme 1 shows the reaction mechanism for EGDMA-crosslinked hydrogels initiated by the photochemical dissociation of the photoinitiator.
Figure 8c,d shows the back and front of the fabric without hydrogel and with hydrogel obtained by the photochemical method. A yellow color on the face of the fabric is clearly observed, indicating the presence of dispersed AgNPs. Figure 8e,f shows the back and front of the fabric without hydrogel and with hydrogel obtained by gamma radiation.
The back side of the fabric also shows a brownish translucent color of AgNPs accumulated on the front side.
Polyethylene Terephthalate Textiles Enhance the Structural Maturation of Human Induced Pluripotent
Discussion
In the present study, PET culture increased sarcomericTNNT2 gene expression compared with hiPSC-CMs cultured on a flat surface. Longer culturing time of hiPS-CM on surfaces providing topographical cues can increase the level of cardiac expression. Our results support this hypothesis: Cultivation of hiPSC-CM on PET textile had a positive effect on cell morphology.
Throughout the study, the attachment of detached hiPS-CMs to the fabric structure was poor. However, textile cultivation had only minor effects on the expression levels of cardiac-specific genes. It was previously speculated that groove edges are particularly important in cell orientation.
Based on the results, culturing hiPSC-CMs on the PET textiles improved their structural properties, such as elongation and sarcomere orientation, as well as enhanced the expression of the sarcomeric genes such as TNNT2.
The Preparation and Characterization of
Polyacrylonitrile-Polyaniline (PAN/PANI) Fibers
Results and Discussion 1. Molecular Weight of Polymers
The fibers obtained as a result of the synthesis of polyaniline in situ in the spinning solution were dark blue (Figure 3c). Deep grooves were clearly visible on the surface of the PAN/PANI in situ fibers. The structure of the PAN/PANI in situ fibers was discontinuous and contained many defects.
However, the linear mass of the PAN/PANI in situ fibers was more than twice as high. However, based on the FTIR results (Figure 5), interactions between these polymers were found, which probably caused a reduction in the interactions between the PAN macromolecules, as well as a significant reduction in the consistency coefficient (Table 1). However, the presence of these polymers causes a decrease in the electrical conductivity of the PANI.
The first derivatives of the TG curve showed that the most moisture was adsorbed in the PAN/PANI fiber in situ.
Enhancing the Dyeability of Polyimide Fibers with the Assistance of Swelling Agents
This assumption was confirmed by characterizing the physical and mechanical properties of PI fibers treated with swelling agents. It was found that the breaking strength and elongation of the PI yarns decreased more or less when the PI fibers were treated with swelling agents. Figure 6 shows the effect of swelling agents on the color strengths of the dyed PI fibers.
It can be seen that the color strength of the dyed PI fibers is more or less improved with the addition of swelling agents. When treated with swelling agents such as MFA, PIP and AP, the dyeability of the PI fibers can be greatly improved. It has been found that swelling agents in amounts greater than 10% (relative to the weight of PI fibers) can penetrate the PI fibers.
PI yarns dyed with the help of blowing agents exhibited good color fastness to washing as tested by color change.
